Main Relay Operation Inspection; Intake Manifold Vacuum Inspection - Mazda MX-5 Miata Sport 2007 Manual

2007 ENGINE PERFORMANCE Symptom Troubleshooting - MX-5 Miata
Pin discoloration (blackness)
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Harness/pin crimp is loose or disconnected.
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If there are no problems, proceed to next investigation below.
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GND System Inspection For Thermistor Type
Confirm that terminal sensor #3 is at 0 V .
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If it is at 0 V , inspect the sensor. If necessary, replace the sensor.
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If not, inspect for the following:
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Open circuit in wiring harness
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Female terminal opening is loose.
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Coupler (pin holder) damage
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Pin discoloration (blackness)
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Harness/pin crimp is loose or disconnected.
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MAIN RELAY OPERATION INSPECTION

1. Verify that the main relay clicks when the ignition switch is turned to ON position and off.
If there is no operation sound, inspect the following:
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Main relay (See RELAY INSPECTION .)
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Harness and connector between battery and main relay terminal A.
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Harness and connector between PCM terminal 1Q and main relay terminal E.
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INTAKE MANIFOLD VACUUM INSPECTION

1. Verify that the intake air hoses are installed securely.
2. Disconnect the vacuum hose connecting the intake manifold and the purge solenoid valve (purge solenoid
valve side) and install the vacuum gauge.
3. Warm up the engine.
4. Measure the intake manifold vacuum while idling (no load) using the vacuum gauge. (See INTAKE
MANIFOLD VACUUM INSPECTION [LF] .)
If not within the specification, perform the following inspections.
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Compression pressure (See COMPRESSION INSPECTION [LF] .)
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Air intake
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2007 Mazda MX-5 Miata Sport
Each hose installation part
Throttle body installation part
Fuel injector installation part
PCV valve installation part
Dynamic chamber installation port
Intake manifold installation part